Apparatus for the compression of gases



April 18, 1939. E. K-AGI APPARATUS FOR THE COMPRESSION OF GASES 2 Sheets-Sheet 1 Filed March 19, 1958 Fgq \NVENTOR Y Emil ffziz 'yz' limmmyadm ATTORNEYS w-ag B imuull OOOOOOG'QO OOQOOOOQO OOOOOO'QO April 18, 1939. E. KAGI 2,155,051

APPARATUS FOR THE COMPRESSION OF GASES I Filed March 19, 1938 2 Sheets-Sheet 2 INVENTOR BY fmzZ KaIgi $214111 v/M ATTO R N EYS Q Patented Apr. 18, 1939 UNITED STATES PATENT OFFICE,

APPARATUS roa THE COMPRESSION or GAS Emil Kiigi, Winterthnr, Switzerland, assignor to Sulzer Freres, Societe Anonyme, Winterthur,

Switzerland Application March 19,

1938, Serial No. 196,866

In Switzerland June 3, 1937 3 Claims.

This invention relates to apparatus'for the compression of gases and has particular appli- 10 the compressor is operating. The invention aims to provide automatic means for preventing the return of compressed gas to the compressor and also the return of lubricant to the compressor when the compressor is stopped.

.216 The apparatus of the invention comprises a compressor connected to a source of gas, a conduit system for passing the compressed gas, together with entrained'or associated lubricant, to a lubricant separator and for returning the sep- 2 arated lubricant to various parts of the compresflow of condensed refrigerant to an evaporator 30 and particularly for stopping the flow of refrigerant from the condenser to the evaporator when the compressor is stopped. In a refrigerating system in which lubricant is separated from the compressed fluid and returned to the 86 compressor, the invention aims to provide valve means controlled by the pressure of the sep-- arated lubricant for controlling the flow of refrigerant from a condenser to an evaporator in dependence upon the compressor operation, and 40 particularly to prevent the flow when the compressor is stopped.- The invention also aims to provide means actuated by the said pressure of the separated lubricant for introducing regulated quantities of liquid refrigerant into the gases passing into the compressor for the pur- I pose of controlling the temperature thereof.

In the accompanying drawings, Fig, 1 is an elevation view, partly in section, of apparatus embodying the invention; a

Fig. 2 is an elevation view, partly in section, 0 apparatus embodying the invention;

Fig. 3 is a detailed sectional view of the comof apparatus embodying the invention as employed in a refrigerating system,

The apparatus, particularly that shown in Fig.

1, comprises a compressor i of the reciprocal piston type having a gas inlet port 2 to which is connected a conduit 3 leading to a source of gas (not shown) such,-for example, as the evaporator of a refrigerating system, and a shut-off valve 4 in the conduit. The exhaust port 5 of the compressor connects to a discharge or delivery ated device 8 and lubricant separator H are con nected in the conduit 6 and the compressed gases from the compressor pass therethrough and to the place where the gases are to be used I such, for example, as a condenserv of a refrigerating system (not shown). The device 8 has a piston 9 which is set in operation by the pressure of gases flowing therethrough from the compressor. The piston has a rod l0 attached thereto connected to a slide valve or piston i3 which operates in a cylinder M. The separator H has a reverse flow baiile I5 which causes the gases to change direction and the oil to be deposited'in the lower portion thereof. The separator may be provided with suitable cooling 2 p means such as the coil I6 through which a cooling fluid may be circulated. The quantity of oil in the lower portion of the separator may be observed by means of a gauge glass IT. A conduit 20 is connected to the lower portion of the separator and the cylinder [4. The pipe or conduit 20 leading from the cylinder I 4 connects to three separate conduits, 2|, 22 and 23, each of which is provided with a regulating valve 24 and observation window 25. The conduit 2| connects to the crankcase of the compressor, the pipe 22 to the inlet port 2, and the conduit 23 to the cylinder of the compressor. The conduit 20 may be providedwith a suitable strainer 26 which is preferably positioned near the lower portion'of 40 the separator. The bottom of the separator may be provided with a valve controlled drain 21.

The crankcase of the compressor is connected by a conduit 28 to the intake port 2 or conduit 3 so that the pressure in the crankcase may be i is sucked through the conduit 3, and the intake port 2, by the compressor and the compressed as, together with its entrained lubricant, forced through the exhaust port 5, the conduit 6, valve 77, the gas controlled device 8, the separator I l, and delivered to its place of use. Due to the conduit 6 having a shut-off valve 7. A gas actul0 pressure of the flowing gas, the piston '9 is shifted, i. e., elevated and the passageway through the device 9 is opened. By reason of the slow flow of the compressed gas in the separator II and the abrupt change in direction, the entrained lubricant or oil is deposited in the bottom. The lubricant in the bottom of the separator has imposed upon its surface the pressure of the gases flo'wing' therthrough, and the lubricant is, accordingly, forced through the pipe 29, and since the piston 9 is in an elevated position, the slide valve I3 is likewise raised and the lubricant is free to flow into and outof the cylinder 14, through the conduit 29 and into the various conduits 2|, 22 and 23. The valves 24 may be separately adjusted for the purpose of controlling the quantity of oil which it is desired to pass through the various conduitsto the compressor. It is to be understood that the lubricant which accumulates in the separator may be passed in the manner indicated to all points of the system requiring lubrication. The lubricant which passes through conduit 22 and enters the port 2 becomes mixed with the gases and upon enter- 25 ing the cylinder of the compressor, it lubricates the piston and upper working-surfaces of the compressor.

' When the compressor 1 stops and there is no gas flowing through the conduit 6, the piston 9 moves downward and causes the slide valve or piston I3 operation. .The closing to close the chamber l4 to the flow of gases through the conduit 29. It is,'accordingly, not possible for lubricant to flow from the separator to the compressor when the compressor is not in of .the passageway through conduit 6 by the downward movement of gas (not 'shown) and an exhaust port 5 connect-.

ing with the conduit.6. The conduit 6 connects on both sides of' the gas actuated device 9 and to a condenser 35. The conduit 6 connects to a chamber or reservoir 36 of the condenser which is formed by the wall 29'. The chamber 36 serves as a reservoir for the accumulation of lubricant carried along with thecompressed vapors or gases The device 9 has a piston- 9 which is movable by the pressure of gas flowing from the compressor.

' therethrough and -a rod HI to which is attached the-slide valve I; mounted in the chamber I4. The lower portion of the reservoir 36 is connected by conduit 29 to the chamber l4. The chamber I4 is connected by conduit 29 to three separate conduits, 31, 39 and 39, each of which has a control valve 24 for regulating the quantity of lubricant passing theretfirough. These conduits, 31, 38 and 39, connect to the bearings-33 and theinlet port 2, respectively. The conduit 29 may be provided with a suitable strainer 26.

A pipe 49 connects the lower portion of the condenser- 35, where liquefied gases accumulate,

and to a control-device 4| and extends to'a place of use of the condensed gas such, for example, as an evaporating unit (not shown) of a refrigerating system. The control device 4| comprises a valve member 42 which is pressed by the spring 43 into engagement with the seat 44. The valve member 42 is connected by a rod 45 to a piston 46 mounted in the cylinder 41 one side of which connects by conduit 49 to the conduit 29 and the other side of which is connected by conduit 49 to the intake conduit 3.

In operating the apparatus of Fig. 2, the gases to be compressed are suckedthrough the intake port 2 from the conduit 3, discharged through the port 5 in a compressed state, passed through the device 9, and the conduit 6, into the condenser 35. The lubricant which has been entrained with the gases during compression 'is separated from the gases and accumulates in the reservoir '36. The lubricant in the reservoir 36 is under the pressure of the compressed gases and the lubricant is, accordingly, forced into conduit 29 and to the chamber l4. When the piston 9 of the device 9 is held in an upright position because of the pressure of gas flowing therethrough, ,the valve l3 opens a passageway through chamber l4. The lubricant is then free to pass from the chamber l4 through the conduit 29 and the various branches thereof, 31, 39 and 39, and be delivered to various parts of the compressor, in a quantity which is selectively determined for each conduit by the regulating valves 24. Since the piston 9 is held in an upright or open position only when gas is flowing through the device 9 from the compressor, the slide valve I3 is, accordingly, only open to the flow of oil from the reservoir 36 to the conduit 29 when the slide valve 13 is held in an upright or open position by the piston 9. When the compressor stops, the piston 9 is depressed and the slide valve l3 closes the passage through chamber l4 to .the flow of oil from the reservoir 36 to the various parts of the compressor, and the depressed position of piston 9 prevents a return of the compressed gas to the compressor.

The compressed and liquefied gases from the .lower portion of the condenser 35 may flow when the compressor is operating and passing gas through the device 9 with suflicient force to raise the piston 9 and open the slide valve l3 and the chamber H to the passage of lubricant through the conduits 29 and 49 to the cylinder 41. The

pressure in the lubricant cylinder 41, when the compressor is in operation, may be .suflicient to overcome the resistance of the spring and depress the valve member 42 thereby enabling the condensed gases to pass through the conduit 49 from the condenser 35. Whenever the compressor stops, the flow of lubricant from the reservoir 36 to the-various parts of the compressor and to the cylinder. 4 'l'is stopped and it is then not possible.

for the condensate-in the condenser 35 to flow through the conduit 49. After starting 'the apparatus,- if an over-pressure arises in the lubricant return pipe behind the chamber l4 against the pressure in the intake pipe 3, the piston 46 is pressed downward against the spring 43, so that the valve member 42 is removed from its seat 44 and the liquefied refrigerant can pass out of conduit 4 9. The control device 4| has the effect that the,valve 42 in pipe 49 leading from the condenser to the place of gas use is held open automatically during the operation of the compressor and remains closed after stoppage of the compressor during the non-operating time. When an evaporator is used, for example, it can not be flooded with the liquid refrigerant which is in the condenser, when the compressor is stopped. When the compressor is again put in operation there is .no danger of inadmissible wet working.

Theapparatus shown in Fig. 4 is similar 'in x the control device 4| and the refrigerant may,

accordingly, pass through the valve opening 44 to the evaporator 50. The cylinder 41 of the device 4| is connected by conduit 48 to the lubricant conduit which receives lubricant from the separator. is connected by the conduit 48 to the intake conduit 8. The pipe 48 has a controlv valve 52 for controlling the quantity of refrigerant passand the slide ,valve or piston I3 is likewise in an ing to the evaporator 50 and has a pipe 53 connected thereto which leads to a regulating valve 54. The regulating valve 54 has a cylinder in which is mounted a piston 56 one end of which is connected to a valve member 51, which engages the seat 58 and is actuated in one direction by the spring 59. One side of the piston 55 connects by conduit 88 to the intake conduit 3, and on the other side to conduit 22. 'The cylinder 55 has an annular channel 6| connecting to a passageway 62 leading into the conduit 88.

In operating the apparatus shown in Fig. 4,

the gases in the evaporator 50 pass through the conduit 3, valve 4 and port 2 into the compressor i, where they are compressed and forced through the exhaust port 5 into the conduit 8. In passing through the conduit 6 the gases must pass through the device 8, thereby raising the piston 9. From the device 8 the gases pass into the sep-' arator I, where the oil is deposited in the bottom and then flow into the condenser 5| where they are liquefied and accumulate in the bottom. when the compressor is inoperation, the piston 9 of the device 8 is in an open or upright position upright or open position, thereby permitting lubricant to flow through the conduit 20 and to be distributed into the various connecting pipes 2|, 22, 23 and 48. Due to the pressure of the lubricant in conduit 48, piston 41 of .the control device 4| is forced downwardly, thereby depress-' ing the spring 43 and moving the valve member 42 awayfrom the seat 44 permitting the condensed refrigerant to pass through the pipe 48 and into the evaporator 50. The passage of the condensed refrigerant from the pipe 48 to the evaporator may be controlled as to quantity by valve 52, and tothe regulating valve 54 by the valve 86. When the compressor is operating, and lubricant permitted to flow through the conduit 20, it may be passed in regulated quantities by means of the valves 24 into the conduit 2|, 22 and 23, and to the cylinder 55. Due to the pressure of the lubricant, the piston 56 is moved to the right against the action of the spring '59 thereby moving the valve member 51 away from the seat 58 and permitting the liquid refrigerant to pass into the port 2 or intake conduit 3. At the same time the lubricant may enter the channel 8| from which it flows through the duct or passageway 62 into the conduit 60, leading to' the port 2 or intake'conduit 3. In this manner, both lubricant and liquid refrigerant may be incorporated in or added to the gases being sucked into the compressor. The liquid refrigerant serves as a cooling medium for the purpose of stabilizing or otherwise regulating the temperature of the compressor and the lubricant may be atomized or dispersed in the gases there- One side of the cylinder'fl' by serving as a lubricant for the upper portion of the compressor cylinder. Since the cylinder 9 of the device 8 is only moved to a position whereby the slide valve or piston l3 opens the passageway through the chamber l4, to the flow of lubricant through the conduit 28 to the control device 4|, or to the regulating device 54, when the compressor is running, the condensed refrigerant is not permitted to flow out of the condenser to the evaporator, or to the compressor, except when the compressor is in operation.

The invention may be applied to plants other than refrigerating plants, for example, to chemical plants or compressed air plants. In a plant there can be present one or more compressors, the

lubricant according to the invention being led back only to a part of the compressors or to all of them. The gas actuated device may be arranged directly in the delivery pipe, or it may be connected thereto by aid of another pipe.

The construction of the individual control or regulating devices can be any desired. The gas actuated device may be arranged separately in space from the'valve it operates. Between the separate devices there may be inserted hydraulic, pneumatic, electric or mechanical transmission devices. Through the lubricant pressure, which is interrupted during the stoppage time, other control devices can also be influenced. The control devices may be closed instead of open dining the operating time andmay be opened only on stoppage. The gas actuated device in the delivery pipe of the compressor may be formed simultaneously as a non-return device in such a way that, after stoppage of the compressor, a backflow of the compressed medium into the compressor is prevented. In the separator or in the pipe leading back from the separator to the compressor there may be installed a float, which shuts off the lubricant return pipe when too little or no more lubricant is present in the separator.

I claim:

1. Apparatus for the compression of gases which comprises means for supplying gas to a compressor, a lubricant separator, deliveryconduit means for passing compressed gas and entrained lubricant from the compressor into the separator, a conduit for returning the separated lubricant to the compressor, a valve in the last named conduit, means actuated by the compressed gas for opening the valve to the flow of lubricant when the compressor is running and for closing the valve when the compressor is stopped, a condenser connected to the separator to receive gases from the compressor, a. valve controlled means for passing the condensate to an evaporating unit, and means operatively connecting the valve controlled means to the means operated by the compressed gas, whereby condensate is passed to the evaporating unit only when the compressor is running.

2. Apparatus for the compression, of gases which comprises a compressor, an evaporator arranged to supply gas to the compressor, a delivery conduit for the discharge of compressed gas and entrained lubricant from the compressor, a separator connected to the delivery conduit for separating lubricant from the compressed gas, a lubricant conduit for returning lubricant from the separator to the compressor, means connected to the delivery conduit responsive to the pressure of gas flowing in the delivery conduit, a valve in the lubricant conduit operated by the means responsive to gas pressure for controlling the flow of lubricant to the compressor, a condenser, means for passing vapor from the separator to the condenser, and a refrigerant conduit connecting the condenser to the evaporator, the said means responsive to the pressure .of flowing gas,

constructed and arranged to control the flow 'of condensateto the evaporator.

3. A refrigerating system which comprises a compressor, a lubricant separator, a condenser, an evaporator, a conduit connecting the intake side of the compressor to the condenser, a gas actuated device responsive to the pressure of gas flowing from the compressor to the separator, a

conduit connecting the condenser to the evaporator, valve control means in the conduit operated by the gas actuated device for opening a passageway in the conduit for the flow of condensate to the evaporator when the compressor is running and for closing the passageway when the compressor is stopped, valve means controlling the flow ofcondensate to the intake side of the compressor, and means operatively connecting the gas actuated device with the last mentioned 10 valve means.

EMIL KAGI. 

